Weld-containing polyarylene sulfide resin molded article

ABSTRACT

A molded article useful for electrical parts, such as connectors, has at least one weld portion and is obtained by injection molding of a polyarylene sulfide composition comprising a polyarylene sulfide and an alkoxysilane such as aminoalkoxysilanes, epoxyalkoxysilanes, mercaptoalkoxysilanes and vinylalkoxysilanes, and optionally an inorganic filler.

FIELD OF THE INVENTION

The present invention relates to a molded article obtained by the injection molding of an improved polyarylene sulfide resin composition. More particularly, the present invention, relates to a molded article obtained by the injection molding of a polyarylene sulfide resin composition which is improved so as to enhance the strength of the weld of said article, such as a connector for electric appliances.

BACKGROUND OF THE INVENTION

Recently, thermoplastic resins having high heat resistance and high chemical resistance have been required as a material for the components of electric, electronic, automobile and chemical apparatus. In this regard, a polyarylene sulfide resins represented by polyphenylene sulfide represents one class resins which meets this requirement. However, polyarylene sulfide resins are disadvantageous in that the part formed by the fusion bonding of the heads of at least two melt flows of the resin joined in a mold cavity during molding (i.e., the weld) exhibits remarkably poor mechanical properties. Therefore, a polyarylene sulfide resin molded article containing a weld tends to break along the weld when subjected to thermal or mechanical stresses. Particularly, a polyarylene sulfide molded article having complicated shape produced by ultrasonic welding is more problematic in this regard. A polyarylene sulfide resin is a material suitable for precision molding, so that a molded article of the resin will necessarily contain a weld in most cases. Accordingly, many attempts have been made to improve the mechanical properties of the weld thereof, among which, the following techniques may be mentioned:

(1) improvement in mold design; for example, a mold having a cold-slug well is used and the corresponding part is cut off after the resulting molded article is cooled. Alternatively, the temperature drop of the material in the fusion bonding section is inhibited by increasing the number of gates or changing the positions of gates,

(2) necessary holes are formed by fabrication to inhibit the formation of a weld during molding,

(3) a composition having an improved fluidity is used (see Japanese Patent Laid-Open Nos. 11357/1984, 11358/1984 and 70157/1982) and

(4) an inorganic filler which effectively enhances the strength of the weld is used (see Japanese Patent Laid-Open No. 70157/1982).

However, these methods have the following problems. That is, according to the method (1), there are many welds which are unavoidable and thus the use of a cold-slug well lowers the production yield.

According to the method (2), the number of processing steps is increased which thereby increases the cost of the molded articles. Although the methods (3) and (4) appreciably improve the mechanical properties of the weld, the strength of the resulting weld is insufficient, so that the molded articles to which the methods can be applied are limited.

Thus, a polyarylene sulfide resin has been used only in limited fields in spite of its high heat resistance and its excellent precision moldability, because it gives a molded article containing welds that exhibit poor mechanical properties.

SUMMARY OF THE INVENTION

The present invention is primarily directed towards overcoming the above disadvantageous with respect to the weld of a polyarylene sulfide resin molded article (which contains a weld as an unavoidable result of the mold design. The molded articles according to this invention include functional precision components having many holes or many bosses, the demand for which has recently increased. One aspect of this invention resides in the discovery that the behavior of the resin at solidification and crystallization is changed by the addition of a specified alkoxysilane, so that the fusion characteristics of the resin in the welding section are improved, which thereby improves the mechanical properties of the weld.

DETAILED DESCRIPTION OF THE INVENTION

The present invention provides a polyarylene sulfide resin molded article containing a weld at least in a part thereof which is obtained by injection molding of a polyarylene sulfide resin composition obtained by adding 0.01 to 5 parts by weight of (B-1) an aminoalkoxysilane or (B 2) an alkoxysilane selected from the group consisting of epoxyalkoxysilanes, mercaptoalkoxysilanes and vinylalkoxysilanes and (C) zero to 400 parts by weight of an inorganic filler to (A) 100 parts by weight of a polyarylene sulfide resin.

The molded article according to this invention has at least one weld portion and is obtained by injection molding of a polyarylene sulfide composition comprising (A) 100 parts by weight of a polyarylene sulfide and 0.01 to 5 parts by weight of an alkoxysilane (B-1) or (B-2).

The composition may further comprise (C) up to 400 parts by weight of an inorganic filler.

It is preferable that the polyarylene sulfide is polyphenylene sulfide or one comprising 90 mole percent or greater of phenylene sulfide units and (B-1) the aminoalkoxysilane has one or more amino groups and two or three alkoxy groups, the alkoxy group having 1 or 2 carbon atoms.

The polyarylene sulfide is polyphenylene sulfide or one comprising 70 mole percent or larger of phenylene sulfide units. The silane compound (B-2) has at least one epoxy, mercapto or vinyl group and two or three alkoxy groups each having 1 to 3 carbon atoms such as methoxy and ethoxy.

In addition, the invention provides parts for an electric instrument, a precision instrument or a chemical apparatus comprising the molded article as defined above.

The resin (A) to be used as a base in the present invention is a polyarylene sulfide resin, which comprises at least 90 molar % of a repeating unit represented by the structural formula: ##STR1## (wherein Ar is an aryl group). A representative example thereof includes polyphenylene sulfide comprising at least 90 molar % of a repeating unit represented by the structural formula: ##STR2## Among them, polyarylene sulfide resins having a melt viscosity as determined at 310° C. and at a shear rate of 1200/sec of 10 to 20000 poise, particularly 100 to 5000 poise are particularly suitable.

The resin to be used as a base in the present invention may contain a small amount of a thermoplastic resin other than a polyarylene sulfide resin as an auxiliary component depending upon the object in addition to a polyarylene sulfide resin as described above. The thermoplastic resin that may be employed is not specifically limited, provided that it is stable at high temperature. Examples thereof include aromatic polyesters prepared from aromatic dicarboxylic acids and diols or aromatic oxycarboxylic acids (for example, polyethylene terephthalate and polybutylene terephthalate), polyamide, polycarbonate, ABS, polyphenylene oxide, polyalkyl acrylate, polyacetal, polysulfone, polyether sulfone, polyether imide, polyether ketone and fluororesins, which may be used as a mixture of two or more of them.

The aminoalkoxysilane (B1) used in the present invention may be any silane compound, provided that it has at least one amino group and two or three alkoxy groups in its molecule. Examples thereof include γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, γ-aminopropylmethyldiethoxysilane, γ-aminopropylmethyldimethoxysilane, N-β(aminoethyl)-γ-aminopropyltriethoxysilane, N-β(aminoethyl)-γ-aminopropyltrimathoxysilane, N-β(aminoethyl)-γaminopropylmethyldiethoxysilane, N-β(aminoethyl)-γ-aminopropylmethyldimethoxysilane, N-phenyl-γ-aminopropyltriethoxysilane and N-phenyl-γ-aminopropyltrimethoxysilane, among which γ-aminopropyltriethoxysilane and γ-aminopropyltrimethoxysilane are particularly preferred.

The component (B2) blended in the composition according to the present invention is one or more silane selected from among epoxyalkoxysilanes, mercaptoalkoxysilanes, and vinylalkoxysilanes. Any epoxyalkoxysilane is effective in so far as it is a silane compound having at least one epoxy group and two or three alkoxyl groups per molecule thereof. Examples of such an epoxyalkoxysilane include γ-glycidoxypropyltrimethoxysilane, β-(3,4-epoxycyclohexyl) ethyltrimethoxysilane, and γ-glycidoxypropyltriethoxysilane. Any mercaptoalkoxysilane is effective in so far as it is a silane compound having at least one mercapto group and two or three alkoxyl groups per molecule thereof. Examples of such a mercaptoalkoxysilane include γ-mercaptopropyltriethoxysilane. Any vinylalkoxysilane is effective in so far as it is a silane compound having at least one vinyl group and two or three alkoxyl groups per molecule thereof Examples of such a vinylalkoxysilane include vinyltriethoxysilane, vinyltrimethoxysilane, and vinyltris(β-methoxyethoxy)silane.

The amount of the above-mentioned alkoxysilane to be used in the present invention is 0.01 to 5 parts by weight, preferably 0.1 to 2 parts by weight, per 100 parts by weight of the polyarylene sulfide resin. When it is less than 0.01 part by weight, the beneficial weld strengthening effects cannot be obtained. When it is excessive, the mechanical properties of the resulting molding are unfavorably poor.

According to the present invention, the inorganic filler (C) is not always essential. However, the addition thereof is preferred to obtain a molded article excellent in mechanical strength, heat resistance, dimensional stability (resistance to deformation and warpage), electric properties and so on. Depending upon the object, a fibrous, powdery, granular or flaky inorganic filler may be used as the component (C).

Examples of the fibrous inorganic filler include glass fiber, asbestos fiber, carbon fiber, silica fiber, silica/alumina fiber, alumina fiber, zirconia fiber, boron nitride fiber, silicon nitride fiber, boron fiber, potassium titanate fiber and fibrous materials of metals such as stainless steel, aluminum, titanium, copper or bass, among which glass fiber and carbon fiber are representative. Further, a high-melting organic fibrous material such as polyamide, fluororesin, polyester resin or acrylic resin may be used.

Examples of the powdery and granular fillers include carbon black, silica, quartz powder, glass bead, glass powder, silicates such as calcium silicate, aluminum silicate, kaolin, talc, clay, diatomaceous earth and wollastonite; metal oxides such as iron oxides, titanium oxide, zinc oxide and alumina; metal carbonates such as calcium carbonate and magnesium carbonate; metal sulfates such as calcium sulfate and barium sulfate; silicon carbide, silicon nitride, boron nitride and various metal powders.

Examples of the flaky filler include mica, glass flake and various metal foils.

These inorganic fillers may be used either alone or as a mixture of them. The simultaneous use of a fibrous filler, particularly glass or carbon fiber, and a granular and/or flaky filler is preferred in order to improve the mechanical strength, dimensional accuracy and electric properties of the composition simultaneously.

When an inorganic filler as described above is used, it is preferred to use an integrating or finishing agent therewith. Examples of the integrating of finishing agent include functional compounds such as epoxy, isocyanate, silane and titanate compounds. These functional compounds may be used in a state adhering to an inorganic filler as a finishing or integrating agent or may be added together with an inorganic filler in preparing the composition.

The amount of the inorganic filler used per 100 parts by weight of the polyarylene sulfide resin used is 0 to 400 parts by weight, preferably 10 to 250 parts by weight. If the amount is less than 10 parts by weight, the mechanical strength will be poor, while if the amount is too large, the molding operation will be troublesome to give a molded article problematic in mechanical strength.

The composition according to the present invention may further contain known substances which are ordinarily added to thermoplastic or thermosetting resins. Namely, the composition may suitably contain a stabilizer such as antioxidant or ultraviolet absorber, antistatic agent, flame retardant, coloring agent such as dye or pigment, lubricant or crystallization accelerator (nucleating agent) depending upon the required performances.

The polyarylene sulfide resin composition according to the present invention can be prepared with an ordinary equipment for the preparation of a synthetic resin composition and by an ordinary process therefor. That is, the polyarylene sulfide resin composition can be prepared by a process which comprises mixing the required components and kneading and extruding the obtained mixture with a single-or twin-screw extruder to obtain a pellet. In this process, a portion of the required components may be mixed as a master batch, followed by the molding of the obtained mixture.

The molded article containing weld at least in a part thereof according to the present invention is a molded article which is produced by injection molding and contains, at least in a part thereof, a weld formed by the fusion bonding of the heads of at least two melt flows of the resin joined in a mold cavity. Such a weld tends to be formed when a molded article has void or when a molded article has differing thicknesses such that the resin material cannot always be made to flow from the thick part to the thin part in the mold cavity. Further, the formation of a weld is unavoidable when the mold used has two or more gates or when a ring-shaped, cylindrical or square-tubular article is molded using a mold having one gate. Such a weld generally appears as a linear mottle or a visibly perceptible region of joined resin flows on the surface of a molded article.

The molded article containing such a weld include various functional components, for example, electronic components such as coil bobbins, print bases and chassis for electronic components; components for electric heater such as lamp sockets, drier grilles, thermostat bases and thermostat cases; motor components such as brush holders, bearing and motor cases; precision components such as pawls for duplicating machines, diaphragms for cameras and cases and base plates of watches; automobile components such as exhaust gas-circulating valves, carburetors, terminal blocks of oil meters and housings of tachometers and batteries and components for chemical equipment such as cleaning frames, insulators, pipe blankets, pump casings and tower fillers.

Although these functional components do not necessarily always have a weld at least in a part thereof, it is difficult from the viewpoint of their functionality to avoid the formation of weld. Further, the above functional components are only examples of the molded articles according to the present invention, i.e., the molded articles are not limited to the specific articles mentioned above.

There are many small and large molded articles containing welds other than the above-mentioned functional components. The present invention relates to all weld-containing polyarylene sulfide molded articles, which include functional components as described above and other weld-containing articles, and seeks to overcome the strength disadvantages of the article's weld by adding a specified amount of an aminoalkoxysilane. Thus, the present invention is remarkably effective in enhancing the practical strength of many molded articles.

It can be understood from the above description and the Examples which follow, that the weld-containing polyarylene sulfide resin molded article according to the present invention has the advantages which will be described below. That is, according to the present invention, the disadvantages with respect to the weld of the polyarylene sulfide resin molded articles according to the prior art are overcome to thereby give polyarylene sulfide resin molded articles having a remarkably enhanced practical strength, which will contribute to improved performances of various functional components. For example,

(1) the weld strength is enhanced by 1.2 to 1.5 times,

(2) the critical deformation of a molded hole in forcing a pin thereinto is enhanced to reduce pin breakage in which thereby reduces the number of rejected products formed in the assembly and

(3) the self-tap strength of a molded hole is enhanced, so that components which have been tapped up to this time can be assembled by self-tap, thus the number of processing steps being reduced.

The connector of the present invention is composed of components as described above and can be easily and economically advantageously produced by mixing the components, melting and kneading the obtained mixture with a single- or twin-screw extruder to obtain a pellet and injection-molding the pellet. The procedure for producing a connector is not however limited to the above procedure, but includes a process which comprises preparing a master batch comprising part of the components, mixing this master batch with the residual part thereof and molding the obtained mixture. Although the shape, dimensions and the number of electrodes of the connector according to the present invention are not limited, the effect of the present invention is particularly remarkable for a connector having a number of electrodes, because such a connector typically has a number of welds and thus a number of corresponding sites for flash formation.

It can be understood from the above description and the following Examples that the connector of the present invention has the following advantages:

(1) the connector is improved in various strengths, particularly in the critical strength of press fitting of a pin, which is one of the important properties of a connector. Accordingly, the disadvantage of the polyarylene sulfide resin connector according to the prior art (i.e., that it tends to break when a pin is press fitted thereinto) can be solved to reduce rejected parts,

(2) the generation of flash is reduces and thus a flash removing step may be avoided, which is economically advantageous, and

(3) the connector can withstand temperatures at which solder melts, because it is formed of polyarylene sulfide resin as a base material. Therefore, the connector can be applied to the fields of surface mounting technology.

The present invention will now be described in more detail by referring to the following nonlimiting Examples.

USE OF AMINOALKOXYSILANE Example 1

γ-Aminopropyltriethoxysilane was added to a polyphenylene sulfide resin (mfd. by Kureha Chemical Industry Co., Ltd.; "Fortron KPS") in an amount given in Table 1, followed by the premixing with a Henschel mixer for 5 minutes. A commercially available glass fiber having a diameter of 13 μm and a length of 3 mm was added to the obtained premix in an amount given in Table 1, followed by the mixing for 2 minutes. The obtained mixture was pelletized with an extruder having a cylinder temperature of 310° C. The obtained pellet was injection molded at a cylinder temperature of 320° C. and at a mold temperature of 150° C. by using a mold having two gates so as to provide a test piece for tensile testing containing a weld in its center. The obtained test piece was examined for strength and elongation of the weld in tension. The results are shown in Table 1.

Comparative Example 1

A pellet was prepared by the same process as that described in Example 1 except that γ-aminopropyltriethoxysilane was not used. This pellet was molded into a test piece, followed by the examination thereof for strength and elongation of the weld in tension in a similar manner to that used in Example 1. The results are shown in Tables 1 and 2.

Examples 2 to 5

A pellet was prepared by the same process as that described in Example 1 except that an aminoalkoxysilane given in Table 2 was used instead of the γ-aminopropyltriethoxysilane. This pellet was molded into a test piece, followed by the examination thereof for strength and elongation of the weld in tension in a similar manner to that used in Example 1. The results are shown in Table 2.

Examples 6 to 8 and Comparative Examples 2 to 4

The same procedure as that described in Example 1 was repeated except that the γ-aminopropyltriethoxysilane and the glass fiber were replaced by those given in Table 3 respectively. The results are shown in Table 3.

Examples 9 to 11 and Comparative Examples 5 to 7

The same procedure as that described in Example 1 was repeated except that γ-aminopropyltriethoxysilane and glass fiber were used each in an amount given in Table 4. The results are shown in Table 4.

Example 12 and Comparative Example 8

The pellets prepared in Examples 1 to 4 and Comparative Example 1 were molded with an injection machine at a cylinder temperature of 320° C. and at a mold temperature of 150° C. into cylindrical bearings having an inside diameter of 11 mmφ and an outside diameter of 12.5 mmφ.

A steel ball having a diameter of 14.2 mmφ was forced into the obtained bearing to determine the breaking strength. The results are shown in Table 5.

Example 13 and Comparative Example 9

The pellets prepared in Examples 1 to 4 and Comparative Example 1 were molded with an injection machine at a cylinder temperature of 320° C. and at a mold temperature of 150° C. into circular perforated plates (inside diameter 30 mmφ, outside diameter 80 mmφ, thickness 3 mmφ, one pin gate).

The obtained plates were examined for weld breaking strength with a three-point bending tester. The results are shown in Table 6.

                                      TABLE 1                                      __________________________________________________________________________     (Example 1 and Comparative Example 1)                                                 polyphenylene                                                                           γ-aminopropyl-     weld elongation                              sulfide resin                                                                           triethoxysilane                                                                         glass fiber                                                                             weld strength                                                                         at break                                     (parts by weight)                                                                       (parts by weight)                                                                       (parts by weight)                                                                       [kg/cm.sup.2 ]                                                                        [%]                                   __________________________________________________________________________     Example 1-1                                                                           100      0.1      70       550    0.4                                   Example 1-2                                                                           100      0.3      70       670    0.5                                   Example 1-3                                                                           100      0.5      70       720    0.7                                   Example 1-4                                                                           100      1.0      70       780    0.7                                   Example 1-5                                                                           100      2.0      70       750    0.6                                   Comparative                                                                           100      --       70       500    0.3                                   Example 1                                                                      __________________________________________________________________________

                                      TABLE 2                                      __________________________________________________________________________     (Examples 2 to 5 and Comparative Example 1)                                           Polyarylene sulfide                 weld elongation                            resin     aminoalkoxysilane                                                                        glass fiber                                                                             weld strength                                                                         at break                                   (parts by weight)                                                                        (parts by weight)                                                                        (parts by weight)                                                                       [kg/cm.sup.2 ]                                                                        [%]                                 __________________________________________________________________________     Example 2                                                                             100       γ-aminopropyl-                                                                     70       760    0.7                                                  trimethoxysilane                                                               (1.0)                                                         Example 3                                                                             100       γ-aminopropyl-                                                                     70       650    0.5                                                  methyldiethoxy-                                                                silane                                                                         (1.0)                                                         Example 4                                                                             100       N-β(aminoethyl)-                                                                    70       640    0.5                                                  γ-aminopropyl-                                                           trimethoxysilane                                                               (1.0)                                                         Example 5                                                                             100       N-phenyl-γ-amino-                                                                  70       670    0.5                                                  propyltrimethoxy-                                                              silane                                                                         (1.0)                                                         Comparative                                                                           100       --        70       500    0.3                                 Example 1                                                                      __________________________________________________________________________

                                      TABLE 3                                      __________________________________________________________________________     (Examples 6 to 8 and Comparative Examples 2 to 4)                                                                              weld                                  polyphenylene                                                                           γ-aminopropyl-       weld elonga-                               sulfide resin                                                                           triethoxysilane                                                                         inorganic filler                                                                        inorganic filler                                                                        strength                                                                            tion at                               (parts by weight)                                                                       (parts by weight)                                                                       (parts by weight)                                                                       (parts by weight)                                                                       [kg/cm.sup.2 ]                                                                      break [%]                      __________________________________________________________________________     Example 6                                                                             100      1.0      glass fiber                                                                             CaCO.sub.3                                                                              620  0.5                                                     (100)    (average par-                                                                  ticle size 4 μm)                                                            (100)                                        Comparative                                                                           "        --       glass fiber                                                                             CaCO.sub.3                                                                              530  0.3                            Example 2                (100)    (average par-                                                                  ticle size 4 μm)                                                            (100)                                        Example 7                                                                             100      1.0      glass fiber                                                                             talc     480  0.3                                                     100      (average par-                                                                  ticle size 10 μm)                                                           (100)                                        Comparative                                                                           "        --       glass fiber                                                                             talc     340  0.2                            Example 3                (100)    (average par-                                                                  ticle size 10 μm)                                                           (100)                                        Example 8                                                                             100      1.0      cargon fiber                                                                            --       680  0.5                                                     (diameter 7 μm,                                                             length 6 mm)                                                                   (40)                                                  Comparative                                                                           "        --       cargon fiber                                                                            --       520  0.3                            Example 4                (diameter 7 μm,                                                             length 6 mm)                                                                   (40)                                                  __________________________________________________________________________

                                      TABLE 4                                      __________________________________________________________________________     (Examples 9 to 11 and Comparative Examples 5 to 7)                                    polyphenylene                                                                           γ-aminopropyl-     weld elongation                              sulfide resin                                                                           triethoxysilane                                                                         glass fiber                                                                             weld strength                                                                         at break                                     (parts by weight)                                                                       (parts by weight)                                                                       (parts by weight)                                                                       [kg/cm.sup.2 ]                                                                        [%]                                   __________________________________________________________________________     Example 9                                                                             100      1.0      0        750    1.0                                   Comparative                                                                           "        --       "        530    0.6                                   Example 5                                                                      Example 10                                                                            100      1.0      30       730    0.6                                   Comparative                                                                           "        --       "        620    0.5                                   Example 6                                                                      Example 11                                                                            100      1.0      150      680    0.5                                   Comparative                                                                           "        --       "        500    0.3                                   Example 7                                                                      __________________________________________________________________________

                                      TABLE 5                                      __________________________________________________________________________     (Example 12 and Comparative Example 8)                                                polyphenylene                                                                           γ-aminopropyl       breaking strength                           sulfide resin                                                                           triethoxysilane                                                                         glass fiber      in forcing                                  (parts by weight)                                                                       (parts by weight)                                                                       (parts by weight)                                                                       molded article                                                                         [kg]                                 __________________________________________________________________________     Example 12                                                                            100      1.0      70       cylindrical                                                                            45                                                                     bearing                                                                        (inside diameter                                                               11φ, outside                                                               diameter 12.5φ)                          Comparative                                                                           "        --       "        cylindrical                                                                            39                                   Example 8                         bearing                                                                        (inside diameter                                                               11φ, outside                                                               diameter 12.5φ                           __________________________________________________________________________

                                      TABLE 6                                      __________________________________________________________________________     (Example 13 and Comparative Example 9)                                                                                    bending                                    polyphenylene                                                                           γ-aminopropyl        strength                                                                            deformation                           sulfide resin                                                                           triethoxysilane                                                                         glass fiber       at break                                                                            at break                              (parts by weight)                                                                       (parts by weight)                                                                       (parts by weight)                                                                       molded article                                                                          [kg] [mm]                           __________________________________________________________________________     Example 13                                                                            100      1.0      70       circular plate                                                                          300  1.9                                                              (perforated)                                                                   (inside diameter                                                               30φ,                                                                       outside diameter                                                               80φ,                                                                       thickness 3 mm)                              Comparative                                                                           "        --       "        circular plate                                                                          180  1.1                            Example 9                         (perforated)                                                                   (inside diameter                                                               30φ,                                                                       outside diameter                                                               80φ,                                                                       thickness 3 mm)                              __________________________________________________________________________

USE OF OTHER AMINOALKOXSILANE Example 14

γ-Glycidoxypropyltrimethoxysilane was added in an amount as shown in Table 7 to a polyphenylene sulfide resin (manufactured by Kureha Chemical Industry Co., Ltd., trade name: "Fortlon KPS"), followed by preliminary mixing with a Henschel mixer for 5 minutes. A commercially available glass fiber (diameter: 13 μm, length: 3 mm) was further added in an amount as shown in Table 7 to the resulting mixture, followed by mixing for 2 minutes. The resulting polyphenylene sulfide resin composition were pelletized using an extruder at a cylinder temperature of 310° C. Subsequently, a tensile test piece was molded using an injection molding machine and a test piece mold provided with two side gates designed so as to form a weld in the middle of a tensile test piece at a cylinder temperature of 320° C. and at a mold temperature of 150° C. The tensile strength and elongation of the weld of the test piece were measured. For reference, a test piece having no weld was molded using a mold provided with one gate and the same measurement as that mentioned above was conducted. The results are shown in Table 7.

Comparative Example 10

Test pieces were prepared in substantially the same respective manners as those of Example 14 except that no γ-glycidoxypropyltrimethoxysilane was used to measure the tensile strengths and elongations of the test pieces. The results are shown in Table 7 to 10.

Example 15

Test pieces were prepared in substantially the same respective manners as those of Example 14 except that γ-mercaptopropyltrimethoxysilane was used as a silane compound to measure the tensile strengths and elongations of the test pieces. The results are shown in Table 8.

Example 16

Test pieces were prepared in substantially the same respective manners as those Example 14 except that vinyltrimethoxysilane was used as a silane compound to measure the tensile strengths and elongations of the test pieces. The results are shown in Table 9.

Example 17 to 21

A test piece having a weld was prepared in substantially the same manner as that of Example 14 except that a material as shown in Table 13 was used as a silane compound to measure the tensile strength and elongation of the weld of the test piece were measured. The results are shown in Table 13.

Examples 22 to 24 and Comparative Examples 11 to 13

A test piece having a weld was prepared in substantially the same manner as that of Example 14 except that respective materials as shown in Table 11 were used as an epoxyalkoxysilane and an inorganic filler to measure the tensile strength and elongation of the weld of the test piece. The results are shown in Table 11.

Examples 25 to 27

A test piece having a weld was prepared in substantially the same manner as that of Example 14 except that respective materials as shown in Table 12 were used as a mercaptoalkoxysilane and an inorganic filler to measure the tensile strength and elongation of the weld of the test piece. The results are shown in Table 12.

Examples 28 to 30

A test piece having a weld was prepared in substantially the same manner as that of Example 14 except that respective materials as shown in Table 13 were used as a vinylalkoxysilane and an inorganic filler to measure the tensile strength and elongation of the weld of the test piece. The results are shown in Table 13.

Examples 31 to 36 and Comparative Examples 14 and 15

A test piece having a weld was prepared in substantially the same manner as that of Example 14 except that a silane compound and a glass fiber were used in respective amounts as shown in Table 14 to measure the tensile strength and elongation of the weld of the test piece. The results are shown in Table 14.

Examples 37 to 39 and Comparative Example 13

Pellets were prepared in substantially the same manner as that of Example 14 except that a silane compound and a glass fiber were used in respective amounts as shown in Table 15. Subsequently, a cylindrical bearing (inner diameter: 11 mmφ, outer diameter: 12.5 mmφ) was molded using an injection molding machine at a cylinder temperature of 320° C. and at a mold temperature of 150° C. The breaking strength of the obtained molding exhibited when a steel ball having a diameter of 14.2 mmφ was pressed into the hole of the molding was measured. The results are shown in Table 15.

Examples 40 to 42 and Comparative Example 17

Pellets were prepared in substantially the same manner as that of Example 14 except that a silane compound and a glass fiber were used in respective amounts as shown in Table 16. Subsequently, a disk having a hole (inner diameter: 30 mmφ, outer diameter: 80 mmφ, thickness: 3 mm, one-point pin gate) was molded using an injection molding machine at a cylinder temperature of 320° C. and at a mold temperature of 150° C. The breaking strength in bending and breaking deformation of the obtained molding was measured by setting the weld of the molding on a three-point bending strength tester. The results are shown in Table 16.

Examples 43 to 48

A silane compound given in Table 17 was added to a polyphenylene sulfide resin (mfd. by Kureha Chemical Industry Co., Ltd.; trade name "Fortron KPS") in an amount given in Table 17, followed by premixing with a Henschel mixer for 5 minutes. A commercially available glass fiber having a diameter of 13 μm and a length of 3 mm was added to the premix in an amount given in Table 17. The obtained mixture was mixed for 2 minutes and pelletized with an extruder at a cylinder temperature of 310° C. The obtained polyphenylene sulfide resin composition pellet was molded with an injection machine at a cylinder temperature of 320° C. and a mold temperature of 150° C. to obtain a connector having a width of 10 mm, a thickness of 5 mm and a length of 85 mm and 72 holes. This connector was examined for flexural breaking strength with a three-point bending tester. Further, the length of the flash generated in a clearance of 20 μ around an ejector pin was measured.

The above pellet was molded with an injection machine at a cylinder temperature of 320° C. and a mold temperature of 150° C. into a connector of 18 pins having a terminal hole size of 0.70 mm. A tapered pin having a tip of 0.30 mm, a rear end of 6 mm, a length of 30 mm and a thickness of 0.58 mm was press fitted into the terminal hole at a rate of 200 m/min to determine the strength at breaking. The results are shown in Table 17.

Comparative Example 18

A pellet was prepared in the same manner as that described in Examples 43 to 48 except that no silane compound was used and molded into a connector by the use of the same mold as that used in example 43. The obtained connector was examined for flexural breaking strength with a three-point bending tester. Further, the length of the flash generated around an ejector pin was measured. Then, the same connector for pin-press-fitting test as that described in Examples 43 to 48 was prepared by the use of the pellet and examined for breaking strength at press fitting a pin into its hole. The results are shown in Tables 17 to 20.

Example 49

The same procedure as that described in Example 43 was repeated except that the silane compound was replaced with γ-aminopropyltriethoxysilane in an amount given in Table 18 to obtain a connector. This connector was examined for flexural breaking strength and flash length. Further, the breaking strength at press fitting of a pin was determined. The results are shown in Table 18.

Example 50

The same procedure as that described in Example 45 was repeated except that the silane compound was replaced with γ-glycidoxypropyltrimethoxysilane in an amount give in Table 19 to obtain a connector. This connector was examined for flexural breaking strength and flash length. Further, the breaking strength at press fitting of a pin was determined. The results are shown in Table 19.

Example 51

The same procedure as that described in Example 47 was repeated except that the silane compound was replaced with vinyltrimethoxysilane in an amount given in Table 20 to obtain a connector. This connector was examined for flexural breaking strength and flash length. Further, the breaking strength at press fitting of a pin was also determined. The results are shown in Table 20.

Examples 52 to 60 and Comparative Examples 19 to 21

The same procedure as that described in Examples 43 to 48 was repeated except that a silane compound and an inorganic filler given in Table 21 were used in amounts given in Table 21 as the components (B) and (C), respectively, to obtain a connector. This connector was examined for flexural breaking strength and flash length. Further, the breaking strength at press fitting of a pin was determined. Results are shown in Table 21.

Examples 61 to 66 and Comparative Examples 22 and 23

the same procedure as that described in Examples 43 to 48 was repeated except that a silane compound and glass fiber given in Table 22 were used in amounts given in Table 22 to obtain a connector. This connector was examined for flexural breaking strength and flash length. Further, the breaking strength at press fitting of a pin was also determined. Results are shown in Table 22.

Examples 67 and 68 and Comparative Examples 24 and 25

The pellets prepared in Example 43 and Comparative Example 43 were molded into various articles given in Table 23. The obtained articles were examined for flexural breaking strength. The results are shown in Table 23.

                                      TABLE 7                                      __________________________________________________________________________                                            Breaking                                                                             Strength of                              Polyphenylene                                                                         γ-Glycidoxypropyl- elongation                                                                           test piece                               sulfide resin                                                                         trimethoxysilane                                                                         Glass fiber                                                                          Strength of weld                                                                        of weld                                                                              having no weld                           [wt. pt.]                                                                             [wt. pt.] [wt. pt]                                                                             [kg/cm.sup.2 ]                                                                          [%]   [kg/cm.sup.2 ]                    __________________________________________________________________________     Ex. 14-1                                                                              100    0.1       70    550      0.4   1730                              Ex. 14-2                                                                              100    0.3       70    620      0.5   1750                              Ex. 14-3                                                                              100    0.5       70    660      0.5   1770                              Ex. 14-4                                                                              100    1.0       70    720      0.6   1790                              Ex. 14-5                                                                              100    2.0       70    680      0.5   1760                              Comp. Ex. 10                                                                          100    --        70    500      0.3   1730                              __________________________________________________________________________

                                      TABLE 8                                      __________________________________________________________________________                                            Breaking                                                                             Strength of                              Polyphenylene                                                                         γ-Mercaptopropyl-  elongation                                                                           test piece                               sulfide resin                                                                         trimethoxysilane                                                                         Glass fiber                                                                          Strength of weld                                                                        of weld                                                                              having no weld                           [wt. pt.]                                                                             [wt. pt.] [wt. pt.]                                                                            [kg/cm.sup.2 ]                                                                          [%]   [kg/cm.sup.2 ]                    __________________________________________________________________________     Ex. 15-1                                                                              100    0.1       70    530      0.3   1720                              Ex. 15-2                                                                              100    0.3       70    650      0.5   1750                              Ex. 15-3                                                                              100    0.5       70    650      0.5   1770                              Ex. 15-4                                                                              100    1.0       70    710      0.6   1790                              Ex. 15-5                                                                              100    2.0       70    670      0.5   1770                              Comp. Ex. 11                                                                          100    --        70    500      0.3   1730                              __________________________________________________________________________

                                      TABLE 9                                      __________________________________________________________________________                                            Breaking                                                                             Strength of                              Polyphenylene                                                                          Vinyl-                  elongation                                                                           test piece                               sulfide resin                                                                          trimethoxysilane                                                                        Glass fiber                                                                          Strength of weld                                                                        of weld                                                                              having no weld                           [wt. pt.]                                                                              [wt. pt.]                                                                               [wt. pt.]                                                                            [kg/cm.sup.2 ]                                                                          [%]   [kg/cm.sup.2 ]                    __________________________________________________________________________     Ex. 16-1                                                                              100     0.1      70    550      0.4   1730                              Ex. 16-2                                                                              100     0.3      70    600      0.4   1750                              Ex. 16-3                                                                              100     0.5      70    620      0.5   1750                              Ex. 16-4                                                                              100     1.0      70    680      0.4   1760                              Ex. 16-5                                                                              100     2.0      70    590      0.4   1750                              Comp. Ex. 10                                                                          100     --       70    500      0.3   1730                              __________________________________________________________________________

                                      TABLE 10                                     __________________________________________________________________________                                             Breaking                                      Polyphenylene                    elongation                                    sulfide resin                                                                          Silane compound                                                                          Glass fiber                                                                          Strength of weld                                                                        of weld                                       [wt. pt.]                                                                              [wt. pt.] [wt. pt.]                                                                            [kg/cm.sup.2 ]                                                                          [%]                                    __________________________________________________________________________     Ex. 17 100     γ-glycidoxypropyl-                                                                 70    650      0.5                                                   triethoxysilane 1.0                                             Ex. 18 100     β-(3,4-epoxy-                                                                       70    650      0.5                                                   cyclohexyl)ethyltri-                                                           methoxysilane 1.0                                               Ex. 19 100     γ-mercaptopropyl-                                                                  70    630      0.5                                                   triethoxysilane 1.0                                             Ex. 20 100     vinyltri- 70    590      0.4                                                   ethoxysilane 1.0                                                Ex. 21 100     vinyltris(β-methoxy-                                                                70    570      0.4                                                   ethoxy)silane 1.0                                               Comp. Ex. 10                                                                          100     --        70    500      0.3                                    __________________________________________________________________________

                                      TABLE 11                                     __________________________________________________________________________                                                     Breaking                              Polyphenylene                                                                          Epoxy-    Inorganic                                                                            Inorganic        elongation                            sulfide resin                                                                          alkoxysilane                                                                             filler                                                                               filler  Strength of weld                                                                        of weld                               [wt. pt.]                                                                              [wt. pt.] [wt. pt.]                                                                            [wt. pt.]                                                                              [kg/cm.sup.2 ]                                                                          [%]                            __________________________________________________________________________                    γ-glycidoxypropyl-                                                                       CaCO.sub.3                                      Ex. 22 100     trimethoxysilane                                                                         glass fiber                                                                          (average                                                                               620      0.5                                           1.0       100   particle                                                                       size: 4 μm)100                               Comp. Ex. 11                                                                          100     --        glass fiber                                                                          CaCO.sub.3                                                                             530      0.3                                                     100   (average                                                                       particle                                                                       size: 4 μm)100                                              γ-glycidoxypropyl-                                                                       talc                                            Ex. 23 100     trimethoxysilane                                                                         glass fiber                                                                          (average                                                                               450      0.3                                           1.0       100   particle                                                                       size: 4 μm)100                               Comp. Ex. 12                                                                          100     --        glass fiber                                                                          talc    340      0.2                                                     100   (average                                                                       particle                                                                       size: 4 μm)100                                              γ-glycidoxypropyl-                                                                 carbon                                                Ex. 24 100     trimethoxysilane                                                                         fiber 40                                                                             --      670      0.5                                           1.0                                                             Comp. Ex. 13                                                                          100     --        carbon                                                                               --      520      0.3                                                     fiber 40                                              __________________________________________________________________________

                                      TABLE 12                                     __________________________________________________________________________                                                      Breaking                             Polyphenylene      Inorganic                                                                            Inorganic        elongation                           sulfide resin                                                                          Mercaptoalkoxysilane                                                                      filler                                                                               filler  Strength of weld                                                                        of weld                              [wt. pt.]                                                                              [wt. pt.]  [wt. pt.]                                                                            [wt. pt.]                                                                              [kg/cm.sup.2 ]                                                                          [%]                           __________________________________________________________________________                    γ-mercaptopropyl-                                                                         CaCO.sub.3                                     Ex. 25 100     trimethoxysilane                                                                          glass fiber                                                                          (average                                                                               620      0.5                                          1.0        100   particle                                                                       size: 4 μm)100                              Comp. Ex. 11                                                                          100     --         glass fiber                                                                          CaCO.sub.3                                                                             530      0.3                                                     100   (average                                                                       particle                                                                       size: 4 μm)100                                             γ-mercaptopropyl-                                                                         talc                                           Ex. 26 100     trimethoxysilane                                                                          glass fiber                                                                          (average                                                                               440      0.3                                          1.0        100   particle                                                                       size: 4 μm)100                              Comp. Ex. 12                                                                          100     --         glass fiber                                                                          talc    340      0.2                                                     100   (average                                                                       particle                                                                       size: 4 μm)100                                             γ-mercaptopropyl-                                                                   carbon                                               Ex. 27 100     trimethoxysilane                                                                          fiber 40                                                                             --      650      0.5                                          1.0                                                             Comp. Ex. 13                                                                          100     --         carbon                                                                               --      520      0.3                                                     fiber 40                                             __________________________________________________________________________

                                      TABLE 13                                     __________________________________________________________________________                                                     Breaking                              Polyphenylene      Inorganic                                                                            Inorganic       elongation                            sulfide resin                                                                          Vinylalkoxysilane                                                                         filler                                                                               filler Strength of weld                                                                        of weld                               [wt. pt.]                                                                              [wt. pt.]  [wt. pt.]                                                                            [wt. pt.]                                                                             [kg/cm.sup.2 ]                                                                          [%]                            __________________________________________________________________________                                     CaCO.sub.3                                     Ex. 28 100     vinyltrimethoxysilane                                                                     glass fiber                                                                          (average                                                                              600      0.5                                           1.0        100   particle size:                                                                 4 μm) 100                                   Comp. Ex. 11                                                                          100     --         glass fiber                                                                          CaCO.sub.3                                                                            530      0.3                                                      100   (average                                                                       particle size:                                                                 4 μm) 100                                                  vinyltrimethoxysilane                                                                           talc                                           Ex. 29 100     1.0        glass fiber                                                                          (average                                                                              450      0.3                                                      100   particle size:                                                                 4 μm) 100                                   Comp. Ex. 12                                                                          100     --         glass fiber                                                                          talc   340      0.2                                                      100   (average                                                                       particle size:                                                                 4 μm) 100                                                  vinyltrimethoxysilane                                                                     carbon                                               Ex. 30 100     1.0        fiber 40                                                                             --     620      0.5                            Comp. Ex. 13                                                                          100     --         carbon                                                                               --     520      0.3                                                      fiber 40                                             __________________________________________________________________________

                                      TABLE 14                                     __________________________________________________________________________                                              Breaking                                     Polyphenylene                     elongation                                   sulfide resin                                                                          Silane compound                                                                           Glass fiber                                                                          Strength of weld                                                                        of weld                                      [wt. pt.]                                                                              [wt. pt.]  [wt. pt.]                                                                            [kg/cm.sup.2 ]                                                                          [%]                                   __________________________________________________________________________                    γ-glycidoxypropyl-                                        Ex. 31 100     trimethoxysilane                                                                          0     720      1.0                                                  1.0                                                                            γ-mercaptopropyl-                                         Ex. 32 100     trimethoxysilane                                                                          0     720      1.0                                                  1.0                                                                            vinyltrimethoxysilane                                           Ex. 33 100     1.0        0     690      1.0                                   Comp. Ex. 14                                                                          100     --         0     530      0.6                                                  γ-glycidoxypropyl-                                        Ex. 34 100     trimethoxysilane                                                                          150   670      0.5                                                  1.0                                                                            γ-mercaptopropyl-                                         Ex. 35 100     trimethoxysilane                                                                          150   650      0.5                                                  1.0                                                                            vinyltrimethoxysilane                                           Ex. 36 100     1.0        150   610      0.4                                   Comp. Ex. 15                                                                          100     --         150   500      0.3                                   __________________________________________________________________________

                                      TABLE 15                                     __________________________________________________________________________                                               Breaking strength                           Polyphenylene                      in pressing ball                            sulfide resin                                                                          Silane compound                                                                           Glass fiber     into hole                                   [wt. pt.]                                                                              [wt. pt.]  [wt. pt.]                                                                            Molding   [kg]                                 __________________________________________________________________________                                     cylindrical bearing                                           γ-glycidoxypropyl-                                                                        (inner diameter:                               Ex. 37 100     trimethoxysilane                                                                          70    11 mmφ,                                                                              46                                                  1.0              outer diameter:                                                                12.5 mmφ)                                                                  cylindrical bearing                                           γ-mercaptopropyl-                                                                         (inner diameter:                               Ex. 38 100     trimethoxysilane                                                                          70    11 mmφ,                                                                              45                                                  1.0              outer diameter:                                                                12.5 mmφ)                                                                  cylindrical bearing                            Ex. 39 100     vinyltrimethoxysilane                                                                     70    (inner diameter:                                                                         43                                                  1.0              11 mmφ,                                                                    outer diameter:                                                                12.5 mmφ)                                                                  cylindrical bearing                            Comp. Ex. 16                                                                          100     --         70    (inner diameter:                                                                         36                                                                   11 mmφ,                                                                    outer diameter:                                                                12.5 mmφ)                                  __________________________________________________________________________

                                      TABLE 16                                     __________________________________________________________________________                                              Breaking                                     Polyphenylene                     strength                                                                             Breaking                               sulfide resin                                                                          Silane compound                                                                           Glass fiber    in bending                                                                           deformation                            [wt. pt.]                                                                              [wt. pt.]  [wt. pt.]                                                                            Molding  [kg]  [mm]                            __________________________________________________________________________                    γ-glycidoxypropyl-                                                                        disk (perforated)                              Ex. 40 100     trimethoxysilane                                                                          70    (inner diameter:                                                                        310   1.9                                            1.0              30 mmφ,                                                                    outer diameter:                                                                80 mmφ,                                                                    thickness: 3 mm)                                              γ-mercaptopropyl-                                                                         disk (perforated)                              Ex. 41 100     trimethoxysilane                                                                          70    (inner diameter:                                                                        270   1.7                                            1.0              30 mmφ,                                                                    outer diameter:                                                                80 mmφ,                                                                    thickness: 3 mm)                                              vinyltrimethoxysilane                                                                           disk (perforated)                              Ex. 42 100     1.0        70    (inner diameter:                                                                        250   1.5                                                             30 mmφ,                                                                    outer diameter:                                                                80 mmφ,                                                                    thickness: 3 mm)                               Comp. Ex. 17                                                                          100     --         70    disk (perforated)                                                                       180   1.1                                                             (inner diameter:                                                               30 mmφ,                                                                    outer diameter:                                                                80 mmφ,                                                                    thickness: 3 mm)                               __________________________________________________________________________

                                      TABLE 17                                     __________________________________________________________________________     Composition                     Flexural                                       polyphenylene                   breaking                                                                            Flash                                                                              Breaking strength at                  sulfide resin                                                                               silane compound                                                                          inorganic filler                                                                        strength                                                                            length                                                                             press fitting of pin                  (parts by weight)                                                                           (parts by weight)                                                                        (parts by weight)                                                                       [kg] [μm]                                                                            [kg]                                  __________________________________________________________________________     Ex. 43                                                                             100      γ-aminopropyltri-                                                                  glass fiber                                                                             37   80  12.7                                               ethoxysilane                                                                             (diameter: 13 μm,                                                 1.0       length: 3 mm)                                                                  70                                                      Ex. 44                                                                             100      N-β(aminoethyl)-γ-                                                            glass fiber                                                                             38   94  11.9                                               aminopropyltri-                                                                          (diameter: 13 μm,                                                 methoxysilane                                                                            length: 3 mm)                                                        1.0       70                                                      Ex. 45                                                                             100      γ-glycidoxypropyl-                                                                 glass fiber                                                                             34   90  11.3                                               trimethoxysilane                                                                         (diameter: 13 μm,                                                 1.0       length: 3 mm)                                                                  70                                                      Ex. 46                                                                             100      β-(3,4-epoxycyclo-                                                                  glass fiber                                                                             31   111 10.5                                               hexyl)ethyltri-                                                                          (diameter: 13 μm,                                                 methoxysilane                                                                            length: 3 mm)                                                        1.0       70                                                      Ex. 47                                                                             100      vinyltrimethoxy-                                                                         glass fiber                                                                             32   143 11.0                                               silane    (diameter: 13 μm,                                                 1.0       length: 3 mm)                                                                  70                                                      Ex. 48                                                                             100      vinyltris (β-meth-                                                                  glass fiber                                                                             30   161 11.7                                               oxyethoxy)silane                                                                         (diameter: 13 μm,                                                 1.0       length: 3 mm)                                                                  70                                                      Comp.                                                                              100      --        glass fiber                                                                             21   425 7.2                                   Ex. 18                 (diameter: 13 μm,                                                           length: 3 mm)                                                                  70                                                      __________________________________________________________________________

                                      TABLE 18                                     __________________________________________________________________________     Compositon                      Flexural Breaking strength                     polyphenylene γ-aminopropyl-                                                                             breaking                                                                            Flash                                                                              at press fitting                      sulfide resin triethoxysilane                                                                         inorganic filler                                                                        strength                                                                            length                                                                             of pin                                (parts by weight)                                                                            (parts by weight)                                                                       (parts by weight)                                                                       [kg] [μm]                                                                            [kg]                                  __________________________________________________________________________     Ex. 49-1                                                                            100      0.1      glass fiber                                                                             24   199 8.1                                                          (diameter: 13 μm,                                                           length: 3 mm)                                                                  70                                                      Ex. 49-2                                                                            100      0.3      glass fiber                                                                             27   163 8.9                                                          (diameter: 13 μm,                                                           length: 3 mm)                                                                  70                                                      Ex. 49-3                                                                            100      0.5      glass fiber                                                                             32   101 10.3                                                         (diameter: 13 μm,                                                           length: 3 mm)                                                                  70                                                      Ex. 49-4                                                                            100      2.0      glass fiber                                                                             34   172 11.2                                                         (diameter: 13 μm,                                                           length: 3 mm)                                                                  70                                                      Comp.                                                                               100      --       glass fiber                                                                             21   425 7.2                                   Ex. 18                 (diameter: 13 μm                                                            length: 3 mm)                                                                  70                                                      __________________________________________________________________________

                                      TABLE 19                                     __________________________________________________________________________     Composition                      Flexural Breaking strength                    polyphenylene γ-glycidoxypropyl-                                                                          breaking                                                                            Flash                                                                              at press fitting                     sulfide resin trimethoxysilane                                                                         inorganic filler                                                                        strength                                                                            length                                                                             of pin                               (parts by weight)                                                                            (parts by weight)                                                                        (parts by weight)                                                                       [kg] [μm]                                                                            [kg]                                 __________________________________________________________________________     Ex. 50-1                                                                            100      0.1       glass fiber                                                                             25   217 7.9                                                          (diameter: 13 μm,                                                           length: 3 mm)                                                                  70                                                     Ex. 50-2                                                                            100      0.3       glass fiber                                                                             27   188 9.2                                                          (diameter: 13 μm,                                                           length: 3 mm)                                                                  70                                                     Ex. 50-3                                                                            100      0.5       glass fiber                                                                             32   136 10.2                                                         (diameter: 13 μm,                                                           length: 3 mm)                                                                  70                                                     Ex. 50-4                                                                            100      2.0       glass fiber                                                                             35   144 10.7                                                         (diameter: 13 μm,                                                           length: 3 mm)                                                                  70                                                     Comp.                                                                               100      --        glass fiber                                                                             21   425 7.2                                  Ex. 18                  (diameter: 13 μm,                                                           length: 3 mm)                                                                  70                                                     __________________________________________________________________________

                                      TABLE 20                                     __________________________________________________________________________     Compositon                      Flexural Breaking strength                     polyphenylene vinyltrimethoxy-  breaking                                                                            Flash                                                                              at press fitting                      sulfide resin silane   inorganic filler                                                                        strength                                                                            length                                                                             of pin                                (parts by weight)                                                                            (parts by weight)                                                                       (parts by weight)                                                                       [kg] [μm]                                                                            [kg]                                  __________________________________________________________________________     Ex. 51-1                                                                            100      0.1      glass fiber                                                                             26   230 7.8                                                          (diameter: 13 μm,                                                           length: 3 mm)                                                                  70                                                      Ex. 51-2                                                                            100      0.3      glass fiber                                                                             27   207 8.2                                                          (diameter: 13 μm,                                                           length: 3 mm)                                                                  70                                                      Ex. 51-3                                                                            100      0.5      glass fiber                                                                             30   188 9.4                                                          (diameter: 13 μm,                                                           length: 3 mm)                                                                  70                                                      Ex. 51-4                                                                            100      2.0      glass fiber                                                                             30   129 10.3                                                         (diameter: 13 μm,                                                           length: 3 mm)                                                                  70                                                      Comp.                                                                               100      --       glass fiber                                                                             21   425 7.2                                   Ex. 18                 (diameter: 13 μm,                                                           length: 3 mm)                                                                  70                                                      __________________________________________________________________________

                                      TABLE 21                                     __________________________________________________________________________                                                       Breaking                                                                       strength                     Composition                              Flexural at press                     Polyphenylene                            breaking                                                                            Flash                                                                              fitting                      sulfide resin                                                                               silane compound                                                                          inorganic filler                                                                        inorganic filler                                                                        strength                                                                            length                                                                             of pin                       (parts by weight)                                                                           (parts by weight)                                                                        (parts by weight)                                                                       (parts by weight)                                                                       [kg] [μm]                                                                            [kg]                         __________________________________________________________________________     Ex. 52                                                                             100      γ-aminopropyltri-                                                                  glass fiber                                                                             CaCO.sub.3                                                                              20   31  9.2                                       ethoxysilane                                                                             (diameter: 13 μm,                                                                    (average particle                                           1.0       length: 3 mm)                                                                           size: 4 μm)                                                        100      100                                            Ex. 53                                                                             100      γ-glycidoxypropyl-                                                                 glass fiber                                                                             CaCO.sub.3                                                                              21   35  8.6                                       trimethoxysilane                                                                         (diameter: 13 μm,                                                                    (average particle                                           1.0       length: 3 mm)                                                                           size: 4 μm)                                                        100      100                                            Ex. 54                                                                             100      vinyltrimethoxy-                                                                         glass fiber                                                                             CaCO.sub.3                                                                              19   86  8.3                                       silane    (diameter: 13 μm,                                                                    (average particle                                           1.0       length: 3 mm)                                                                           size: 4 μm)                                                        100      100                                            Comp.                                                                              100      --        glass fiber                                                                             CaCO.sub.3                                                                              14   122 5.0                          Ex. 19                 (diameter: 13 μm,                                                                    (average particle                                                     length: 3 mm)                                                                           size: 4 μm)                                                        100      100                                            Ex. 55                                                                             100      γ-aminopropyltri-                                                                  glass fiber                                                                             talc     24   20  9.1                                       methoxysilane                                                                            (diameter: 13 μm,                                                                    (average particle                                           1.0       length: 3 mm)                                                                           size: 10 μm)                                                       100      100                                            Ex. 56                                                                             100      γ-glycidoxypropyl-                                                                 glass fiber                                                                             talc     18   27  9.0                                       trimethoxysilane                                                                         (diameter: 13 μm,                                                                    (average particle                                           1.0       length: 3 mm)                                                                           size: 10 μm)                                                       100      100                                            Ex. 57                                                                             100      vinyltrimethoxy-                                                                         glass fiber                                                                             talc     18   42  7.9                                       silane    (diameter: 13 μm,                                                                    (average particle                                           1.0       length: 3 mm)                                                                           size: 10 μm)                                                       100      100                                            Comp.                                                                              100      --        glass fiber                                                                             talc     13   91  4.8                          Ex. 20                 (diameter: 13 μm,                                                                    (average particle                                                     length: 3 mm)                                                                           size: 10 μm)                                                       100      100                                            Ex. 58                                                                             100      γ-aminopropyltri-                                                                  carbon fiber                                                                            --       43   72  12.0                                      ethoxysilane                                                                             (diameter: 7 μm,                                                  1.0       length: 6 mm)                                                                  40                                                      Ex. 59                                                                             100      γ-glycidoxy-                                                                       carbon fiber                                                                            --       38   90  11.2                                      propyltrimethoxy-                                                                        (diameter: 7 μm,                                                  silane    length: 6 mm)                                                        1.0       40                                                      Ex. 60                                                                             100      vinyltrimethoxy-                                                                         carbon fiber                                                                            --       34   119 9.5                                       silane    (diameter: 7 μm,                                                  1.0       length: 6 mm)                                                                  40                                                      Comp.                                                                              100      --        carbon fiber                                                                            --       26   539 6.7                          Ex. 21                 (diameter: 7 μm,                                                            length: 6 mm)                                                                  40                                                      __________________________________________________________________________

                                      TABLE 22                                     __________________________________________________________________________     Composition                     Flexural Breaking strength                     polyphenylene                   breaking                                                                            Flash                                                                              at press fitting                      sulfide resin                                                                               silane compound                                                                          inorganic filler                                                                        strength                                                                            length                                                                             of pin                                (parts by weight)                                                                           (parts by weight)                                                                        (parts by weight)                                                                       [kg] [μm]                                                                            [kg]                                  __________________________________________________________________________     Ex. 61                                                                             100      γ-aminopropyltri-                                                                  --       13   110 22.0                                               ethoxysilane                                                                   1.0                                                               Ex. 62                                                                             100      γ-glycidoxypropyl-                                                                 --       12   144 20.1                                               trimethoxysilane                                                               1.0                                                               Ex. 63                                                                             100      vinyltrimethoxy-                                                                         --       12   297 19.6                                               silane                                                                         1.0                                                               Comp.                                                                              100      --        --       9    782 14.9                                  Ex. 22                                                                         Ex. 64                                                                             100      γ-aminopropyltri-                                                                  glass fiber                                                                             49   32  10.5                                               ethoxysilane                                                                             (diameter: 13 μm,                                                 1.0       length: 3 mm)                                                                  150                                                     Ex. 65                                                                             100      γ-glycidoxypropyl-                                                                 glass fiber                                                                             47   38  10.4                                               trimethoxysilane                                                                         (diameter: 13 μm,                                                 1.0       length: 3 mm)                                                                  150                                                     Ex. 66                                                                             100      vinyltrimethoxy-                                                                         glass fiber                                                                             42   85  10.0                                               silane    (diameter: 13 μm,                                                 1.0       length: 3 mm)                                                                  150                                                     Comp.                                                                              100      --        glass fiber                                                                             34   180 6.2                                   Ex. 23                 (diameter: 13 μm,                                                           length: 3 mm)                                                                  150                                                     __________________________________________________________________________

                                      TABLE 23                                     __________________________________________________________________________     Composition                             Flexural                               polyphenylene                                                                               γ-aminopropyltri-    breaking                               sulfide resin                                                                               ethoxysilane                                                                            inorganic filler  strength                               (parts by weight)                                                                           (parts by weight)                                                                       (parts by weight)                                                                       Molding article                                                                         [kg]                                   __________________________________________________________________________     Ex. 67                                                                             100      1.0      glass fiber                                                                             rectangular                                                                             101                                                          (diameter: 13 μm,                                                                    connector of                                                          length: 3 mm)                                                                           18 holes                                                              70       (width: 10 mm                                                                  thickness: 5 mm                                                                length: 31 mm)                                  Comp.                                                                              100      --       glass fiber                                                                             rectangular                                                                             84                                     Ex. 24                (diameter: 13 μm,                                                                    connector of 18                                                       length: 3 mm)                                                                           holes                                                                 70       (width: 10 mm                                                                  thickness: 5 mm                                                                length: 31 mm)                                  Ex. 68                                                                             100      1.0      glass fiber                                                                             rectangular                                                                             67                                                           (diameter: 13 μm,                                                                    connector of                                                          length: 3 mm)                                                                           48 holes                                                              70       (width: 10 mm                                                                  thickness: 5 mm                                                                length: 55 mm)                                  Comp.                                                                              100      --       glass fiber                                                                             rectangular                                                                             44                                     Ex. 25                (diameter: 13 μm,                                                                    connector of                                                          length: 3 mm)                                                                           48 holes                                                              70       (width: 10 mm                                                                  thickness: 5 mm                                                                length: 55 mm)                                  __________________________________________________________________________ 

We claim:
 1. An injection molded polyarylene sulfide article having at least one weld portion between at least first and second regions of said article, which weld portion is formed by opposing melt flows during injection molding of said article, said article consisting essentially of a polyarylene sulfide composition comprising (A) 100 parts by weight of a polyarylene sulfide resin, and (B) an amount between 0.01 to 5 parts by weight of an alkoxysilane sufficient to strengthen said weld portion, wherein said alkoxysilane is selected from the group consisting of aminoalkoxysilanes, epoxyalkoxysilanes, mercaptoalkoxysilanes and vinylalkoxysilanes.
 2. A molded article as claimed in claim 1, in which said composition further comprises (C) up to 400 parts by weight of an inorganic filler.
 3. A molded article as claimed in claim 1, in which said alkoxysilane consists of an aminoalkoxysilane.
 4. A molded article as claimed in claim 3, in which the polyarylene sulfide is a polyphenylene sulfide having at least 90 mole percent phenylene sulfide units.
 5. A molded article as claimed in claim 1, in which said alkoxysilane consists of an epoxyalkoxysilane.
 6. A molded article as claimed in claim 3, in which the polyarylene sulfide is a polyphenylene sulfide having at least 70 mole percent phenylene sulfide units.
 7. A molded article as claimed in claim 3, in which the aminoalkoxysilane has one or more amino groups and two or three alkoxy groups, the alkoxy group having 1 or 2 carbon atoms.
 8. A molded article as claimed in claim 5, in which the alkoxysilane compound has at least, one epoxy, mercapto or vinyl group and two or three alkoxy groups each having 1 to 3 carbon atoms.
 9. A molded article as claimed in claim 1 which is in the form of a part for an electric appliance, a precision instrument, or an apparatus for a chemical process.
 10. A molded article as claimed in claim 1, which is in the form of an electrical connector. 